Image sensing apparatus and power managing method

FIELD OF THE INVENTION

0001This invention relates to an image sensing apparatus (such as a digital video camera or digital camera) having a communication interface that is capable of feeding current, such as an interface compliant with the USB (Universal Serial Bus) standard (USB 1.1, USB 2.0, etc.) or one similar thereto, and to a method of managing power in such an image sensing apparatus.

BACKGROUND OF THE INVENTION

0002USB (Universal Serial Bus) standards (USB 1.1 (see “Universal Serial Bus Specification Revision 1.1, Sep. 23, 1998”), USB 2.0 (see “Universal Serial Bus Specification Revision 2.0, Apr. 27, 2000”)) relate to communication interfaces between personal computers and peripherals. A communication interface that complies with the USB standard shall be referred to as a “USB interface” below.

0003A USB interface has a connector for D+ and D− lines, a VBUS line and a GND line. The D+ and D− lines are wires for data transfer, and the VBUS and GND lines are lines for supplying power. The VBUS line is limited to a current of 100 to 500 mA.

0004A bus-powered device and a self-powered device are stipulated by the USB standard. A bus-powered device is a device that operates on power supplied from a host or USB hub via a USB interface. A self-powered device is a device that operates on power supplied from its own main power source (an AC power source or battery).

0005For a description of prior art relating to USB power management, see the specification of Japanese Patent Application Laid-Open No. 2001-75682. This patent reference describes art whereby the power supplied to a device that exceeds the power supply capacity of a host is limited when the device is connected.

0006However, a conventional image sensing apparatus (such as a digital video camera or digital camera) consumes a large amount of power and cannot operate solely on power supplied from a USB interface. In other words, there is not a single conventional image sensing apparatus that can operate as a bus-powered device. This problem also arises with an image sensing apparatus having a communication interface compliant with a standard similar to the USB standard.

SUMMARY OF THE INVENTION

0007Accordingly, an object of the present invention is to provide an image sensing apparatus (such as a digital video camera or digital camera) that is capable of operating as a bus-powered device, as well as a method of managing power in this image sensing apparatus.

0008According to an aspect of the present invention, it is provided an image sensing apparatus comprising: a communication interface; a detecting unit adapted to whether there is supply of power from a main power source or from the communication interface; and a power managing unit adapted to limit power from the communication interface to prescribed components and supplying the power to these limited components in a case where power from the main power source is insufficient and power from the communication interface is sufficient.

0009According to another aspect of the present invention, it is provided a method of managing power in an image sensing apparatus having a communication interface, comprising steps of: detecting whether there is supply of power from a main power source or from the communication interface; and limiting power from the communication interface to prescribed components and supplying the power to these limited components in a case where power from the main power source is insufficient and power from the communication interface is sufficient.

0010Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

0011The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

0012<figref idref="DRAWINGS">FIG. 1</figref> is a block diagram illustrating the structure of a digital video camera according to a first embodiment of the present invention;

0013<figref idref="DRAWINGS">FIG. 2</figref> is a diagram illustrating the digital video camera and a printer in a state connected by a USB according to the first embodiment;

0014<figref idref="DRAWINGS">FIG. 3</figref> is a block diagram illustrating the structure of a printer according to the first embodiment;

0015<figref idref="DRAWINGS">FIG. 4</figref> is a flowchart illustrating the procedure of power management processing executed by the digital video camera according to the first embodiment;

0016<figref idref="DRAWINGS">FIG. 5</figref> is a diagram illustrating an example of a panel display whereby the user of the digital video camera is notified of the fact that camera is running on bus power;

0017<figref idref="DRAWINGS">FIG. 6</figref> is a block diagram illustrating the structure of a digital video camera according to a second embodiment of the present invention;

0018<figref idref="DRAWINGS">FIG. 7</figref> is a diagram illustrating the digital video camera and a personal computer in a state connected by a USB according to the second embodiment; and

0019<figref idref="DRAWINGS">FIG. 8</figref> is a flowchart illustrating the procedure of power management processing executed by the digital video camera according to the second embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

0020Preferred embodiments of the present invention will now be described in detail in accordance with the accompanying drawings.

First Embodiment

0021<figref idref="DRAWINGS">FIG. 1</figref> is a block diagram illustrating the structure of a digital video camera <b>200</b> according to a first embodiment of the present invention.

0022As shown in <figref idref="DRAWINGS">FIG. 1</figref>, the digital video camera <b>200</b> has an input terminal <b>1</b> to which power is supplied from a back-up power source. The power applied to the terminal <b>1</b> is supplied to a system controller <b>8</b> at all times. An input terminal <b>2</b> receives power supplied from a main power source (an AC power source or a battery), and an input terminal <b>3</b> receives power (also referred to as “bus power”) supplied from a USB interface <b>4</b>. The latter is an interface compliant with the above-mentioned USB 1.1 and USB 2.0 standards or standards similar thereto and has a connector for D+ and D− lines, a VBUS line and a GND line. As stipulated by the USB standards, the D+ and D− lines are lines for data transfer, and the VBUS and GND lines are lines for supplying power.

0023A power-source detector <b>5</b> has a function for detecting whether power being supplied to the terminal <b>2</b> from the main power source (not shown) is sufficient or not, and a function for detecting whether power being supplied to the terminal <b>3</b> from the USB interface <b>4</b> is sufficient or not.

0024When closed, a changeover switch <b>6</b> adopts supply of power from the main power source as the power source of the digital video camera <b>200</b>. When closed, a changeover switch <b>7</b> supplies power (bus power) from the terminal <b>3</b> to only to a card controller <b>10</b>, USB controller <b>11</b>, LCD (Liquid Crystal Display) controller <b>12</b>, LCD panel <b>14</b> and character signal generator <b>15</b>.

0025The system controller <b>8</b> executes overall control of the digital video camera <b>200</b> and includes a CPU <b>80</b> and a memory <b>81</b> storing a control program, etc., executed by the CPU <b>80</b>. A control panel <b>9</b> has various switches and keys operated by the user. The LCD panel <b>14</b> also functions as part of the control panel <b>9</b>.

0026The card controller <b>10</b> controls a removably inserted memory card <b>22</b>. Specifically, the card controller <b>10</b> exercises control to record a video signal, which is generated by a camera unit <b>21</b>, on the memory card <b>22</b>, to reproduce the content of the memory card <b>22</b> and deliver the reproduced signal to a signal processor <b>19</b>, whence the signal is processed and output to an AV terminal <b>20</b>, to reproduce the content of the memory card <b>22</b> and deliver the reproduced signal to the LCD controller <b>12</b>, whence the signal is output to the LCD panel <b>14</b>, or to reproduce the content of the memory card <b>22</b> and deliver the reproduced signal to the USB controller <b>11</b>, whence the signal is output to the USB interface <b>4</b>.

0027The USB controller <b>11</b> controls the signal that enters from the USB interface <b>4</b>. The LCD controller <b>12</b> outputs the following signals to the LCD panel <b>14</b>: a character signal generated by character signal generator <b>15</b>, a signal reproduced from the card controller <b>10</b>, a signal, which is reproduced on tape <b>18</b>, from the signal processor <b>19</b>, and a sensed-image signal from the camera unit <b>21</b>. A CVF (Color View Finder) <b>13</b>, which is for being displayed on a finder having an ocular lens, comprises a display element such as an LCD and an optical system. The LCD panel <b>14</b>, on the other hand, which is a so-called liquid crystal monitor, also functions as a finder although it provides display of larger size. A GUI screen such as a menu of various setup items also is displayed on the LCD panel <b>14</b>, which therefore constructs part of the control panel <b>9</b>. The character signal generator <b>15</b> generates a character signal and causes this signal to be displayed upon mixing it with the signal reproduced from the card controller <b>10</b>, the signal reproduced on the tape <b>18</b> from the signal processor <b>19</b> and the sensed-image signal from the camera unit <b>21</b>.

0028A mechanical section controller <b>16</b> controls a mechanical section <b>17</b> in order to record video on the recording tape <b>18</b>, such as a video cassette tape, play back the video signal from the tape <b>18</b>. The mechanical section <b>17</b> has a mechanism, and implements control thereof, for actually running the tape <b>18</b> and rotating heads to thereby record video on and play video back from the tape <b>18</b>. The signal processor <b>19</b> outputs the following signals to the AV terminal <b>20</b>: the character signal produced by the character signal generator <b>15</b>, the reproduced signal from the card controller <b>10</b>, the signal reproduced on the tape <b>18</b> from the mechanical section controller <b>16</b>, and the sensed-image signal from the camera unit <b>21</b>. The AV terminal <b>20</b> outputs the signal from the signal processor <b>19</b>. The camera unit <b>21</b> generates a signal for executing photographic processing in the digital video camera <b>200</b>. A power supply unit <b>23</b> controls the supply of power to the digital video camera <b>200</b> and supplies power to each of the components. A CVF controller <b>25</b> outputs the following signals to the CVF <b>13</b>: the reproduced signal from the card controller <b>10</b>, the signal reproduced on the tape from the signal processor <b>19</b>, and the sensed-image signal from the camera unit <b>21</b>. A USB cable <b>26</b> is for connecting the digital video camera <b>200</b> to a printer, personal computer or other device via the USB interface <b>4</b>.

0029Also illustrated in <figref idref="DRAWINGS">FIG. 1</figref> are a block <b>30</b> to which power is supplied by the back-up power source, a block <b>31</b> to which power is supplied when the switch <b>7</b> is closed, and a block <b>32</b> to which power is supplied when the switch <b>6</b> is closed. It should be noted that power is supplied to both blocks <b>31</b> and <b>32</b> when the switch <b>6</b> is closed, as a result of which the device can operate in the usual fashion as the digital video camera <b>200</b>.

0030<figref idref="DRAWINGS">FIG. 2</figref> is a diagram useful in describing the configuration of a printing system (a direct-print system) for performing printing by a direct connection between the digital video camera <b>200</b> and printer <b>100</b> according to the first embodiment.

0031As illustrated in <figref idref="DRAWINGS">FIG. 2</figref>, the printer <b>100</b>, which is connected to an AC power source, supplies bus power to the digital video camera <b>200</b> in a case where the digital video camera <b>200</b> and the printer <b>100</b> are connected via the USB cable <b>26</b>. In other words, in this USB connection, the printer <b>100</b> serves as the “host” and the digital video camera <b>200</b> as the “device”. In a system having such a configuration, image information that has been recorded on the memory card <b>22</b> is transmitted from the digital video camera <b>200</b> to the printer <b>100</b>, which proceeds to print the image represented by the image information.

0032<figref idref="DRAWINGS">FIG. 3</figref> is a block diagram illustrating the structure of the printer <b>100</b> according to the first embodiment.

0033A USB interface <b>130</b> is one that complies with the USB 1.1 and USB 2.0 standards or standards similar thereto. A USB controller <b>104</b> controls an exchange of signals via the USB in a manner similar to that of the USB controller <b>11</b> in the digital video camera <b>200</b> described above. An image memory <b>108</b> stores encoded image data that has entered from the digital video camera <b>200</b> or print images obtained by decompressing such image data.

0034A color adjusting circuit <b>109</b> adjusts the color of an image to be printed. A tone adjusting circuit <b>110</b> applies tone processing to the image to be printed. A head driver <b>111</b> drives a printer head <b>117</b> in accordance with image data that is output from the tone adjusting circuit <b>110</b>. Printing paper <b>118</b> is a printing medium on which an image is printed. A system controller <b>112</b> controls the overall operation of the printer <b>100</b>. A motor driving circuit <b>113</b> controls the drive of a carriage motor <b>122</b> for causing the printer head <b>117</b> to scan across the printing medium. A motor driving circuit <b>116</b> controls the drive of a sheet feeding motor <b>123</b> for feeding paper. A main switch <b>114</b> includes a power supply switch and keys or switches that allow the user to apply commands to the printer.

0035A display unit <b>115</b> displays information such as information relating to the printer <b>100</b>. A paper-jam detecting circuit <b>119</b> detects jamming of paper based upon an output of a paper sensor or the like. A bus-power supply unit <b>131</b> supplies bus power to the USB interface <b>130</b>. Bus power supplied from the USB interface <b>130</b> is input to the USB interface <b>4</b> through the USB cable <b>26</b> and is used by the digital video camera <b>200</b>. A power supply unit <b>132</b> supplies power to the various blocks constituting the printer <b>100</b>.

0036It should be noted that the printer head <b>117</b> may be one that uses an electromagnetic transducer such as a piezoelectric element as means for generating energy needed to discharge ink, or one that heats a liquid by an electrothermal transducer having a heating resistor. According to the first embodiment, however, the printer head <b>117</b> is of the ink-jet type that discharges a liquid by utilizing thermal energy (i.e., the film-boiling phenomenon).

0037<figref idref="DRAWINGS">FIG. 4</figref> is a flowchart useful in describing the procedure of power management processing executed in the digital video camera <b>200</b> of the first embodiment. The program for executing the processing described in connection with <figref idref="DRAWINGS">FIG. 4</figref> is stored in the memory <b>81</b> of the system controller <b>8</b> and is executed by the CPU <b>80</b> of system controller <b>8</b>. It should be noted that the system controller <b>8</b> for executing this processing is run by back-up power supplied from the back-up power source.

0038First, at step S<b>1</b> in <figref idref="DRAWINGS">FIG. 4</figref>, it is determined whether power being supplied from the main power source to the terminal <b>2</b> is sufficient or not using the result of detection by the power-source detector <b>5</b>. If the power being supplied from the main power source to the terminal <b>2</b> is sufficient, control proceeds to step S<b>2</b>, where the switch <b>7</b> is opened, and then to step S<b>3</b>, where the switch S<b>6</b> is closed. As a result, power from the main power source is supplied to the entire digital video camera <b>200</b> so that the camera can perform fully the usual operations of a digital video camera (step S<b>4</b>).

0039If power being supplied from the main power source to the terminal <b>2</b> is insufficient, the control proceeds to step S<b>5</b>. Here it is determined whether the power being supplied from the USB interface <b>4</b> to the terminal <b>3</b> is sufficient. If the power being supplied from the USB interface <b>4</b> to the terminal <b>3</b> is sufficient, then control proceeds to step S<b>6</b>, where the switch <b>6</b> is opened, and then to step S<b>7</b>, where the switch <b>7</b> is closed. As a result, the power supplied to the USB interface <b>4</b> is supplied to the system controller <b>8</b>, control panel <b>9</b>, card controller <b>10</b>, USB controller <b>11</b>, LCD controller <b>12</b>, LCD panel <b>14</b> and character signal generator <b>15</b> via the switch <b>7</b> (step S<b>8</b>). Further, by opening switch <b>6</b>, supply of power to the block <b>32</b> for controlling the camera unit <b>21</b> and the recording of images on the tape <b>18</b> is halted.

0040At step S<b>8</b>, the digital video camera <b>200</b> starts operating as a bus-powered device. At this time the digital video camera <b>200</b> supplies power only to components necessary for processing (print processing in this case) between itself and the USB host (the printer <b>100</b> in this case).

0041<figref idref="DRAWINGS">FIG. 5</figref> is a diagram illustrating an example of a screen displayed on the LCD panel <b>14</b> in a case where the device is being operated by supply of power from bus power.

0042In this case, an image (<b>401</b>) selected so as to be printed and buttons <b>402</b>, <b>403</b> for designating printing and cancelling printing are displayed, and a message (“OPERATING UNDER BUS POWER”) <b>400</b> indicating that the device is being operated as a bus-powered device is displayed. Thus, the system controller <b>8</b> prohibits the user of the digital video camera <b>200</b> from operating the control panel <b>9</b> to perform an operation other than printing or printing set-up and notifies the user of the fact that the operation of the digital video camera <b>200</b> is being restricted.

0043Next, control proceeds to step S<b>9</b>, where it is determined whether the control panel <b>9</b> has been used to select a print image and whether a print request has been entered by clicking the “PRINT” button <b>402</b> shown in <figref idref="DRAWINGS">FIG. 5</figref>. If a print request has been entered, then control proceeds to step S<b>10</b>, where the selected print data starts being transmitted to the printer <b>100</b>. Accordingly, the card controller <b>10</b> is instructed to perform an operation for reading in image data that has been stored on the memory card <b>22</b>, and the system controller <b>8</b> causes the USB controller <b>11</b> to put the image data from memory card <b>22</b>, which has been read by the card controller <b>10</b>, into the form of data that can be printed by the printer <b>100</b> and to transmit the data from the USB interface <b>4</b> to the printer <b>100</b>. Next, when transmission of the print data ends at step S<b>11</b>, control proceeds to step S<b>12</b>, where the printer <b>100</b> is notified of the fact that transmission of all image data has ended. In response, print processing starts in the printer <b>100</b>.

0044Further, if it is found at step S<b>5</b> that power being supplied from the USB interface <b>4</b> to the terminal <b>3</b> is insufficient, control proceeds to step S<b>13</b> and the switch <b>6</b> is opened. Next, control proceeds to step S<b>14</b>, where switch <b>7</b> is closed. As a result, supply of power to the digital video camera <b>200</b> is terminated.

0045It should be noted that the printer <b>100</b> that has received image data from the digital video camera <b>200</b> forms a print image using the system controller <b>112</b>, stores the image in the image memory <b>108</b>, controls the color adjusting circuit <b>109</b> that adjusts printing control, the tone adjusting circuit <b>110</b> that executes print tone processing, the head driver <b>111</b> that causes the printer head <b>117</b> to print the output image from the tone adjusting circuit <b>110</b>, the motor driving circuit <b>113</b> that moves the printer head <b>117</b> and the motor driving circuit <b>116</b> that drives the paper-feed motor, whereby the specified image is printed on the printing paper <b>118</b>.

0046With the digital video camera <b>200</b> according to the first embodiment as described above, power can be supplied only to limited blocks in a case where power from the main power source is insufficient but power from the USB interface <b>4</b> is sufficient. As a result, even in the absence of a main power source for the digital video camera <b>200</b>, an image recorded on a memory card that has been inserted into the digital video camera <b>200</b> can be output to a printer and printed.

Second Embodiment

0047<figref idref="DRAWINGS">FIG. 6</figref> is a block diagram illustrating the structure of a digital video camera <b>200</b> according to a second embodiment of the present invention. Components in <figref idref="DRAWINGS">FIG. 7</figref> identical with those in <figref idref="DRAWINGS">FIG. 1</figref> are designated by like reference characters and need not be described again.

0048In <figref idref="DRAWINGS">FIG. 6</figref>, the power-source detector <b>5</b> has a function for detecting whether power being supplied to the terminal <b>2</b> from the main power source is sufficient or not, and a function for detecting whether power being supplied to the terminal <b>3</b> from the USB interface <b>4</b> is sufficient or not. When closed, the changeover switch <b>7</b> supplies bus power from the terminal <b>3</b> to the card controller <b>10</b> and USB controller <b>11</b>. An LED <b>61</b> lights in order to indicate to the user the fact that the digital video camera <b>200</b> is running solely on bus power. A CVF &amp; LCD controller <b>63</b> outputs the signal reproduced by the card controller <b>10</b>, the reproduced signal on tape <b>18</b> from the mechanical section controller <b>16</b> and the sensed-image signal from the camera unit <b>21</b> to an LCD panel <b>64</b>.

0049Also illustrated in <figref idref="DRAWINGS">FIG. 6</figref> are a block <b>62</b> to which power is supplied by bus power from the USB connection or from the main power source, and a block <b>65</b> driven by power from the main power source.

0050If the digital video camera <b>200</b> having the structure described above and a personal computer <b>300</b> are connected via a USB cable in the manner shown in <figref idref="DRAWINGS">FIG. 7</figref>, the personal computer <b>300</b> serves as the host and is the side that supplied bus power. The digital video camera <b>200</b> is the device and is the side that receives bus power. With the connections as described, image data can be read from and written to the memory card <b>22</b> of the digital video camera <b>200</b> in response to commands from the personal computer <b>300</b>.

0051<figref idref="DRAWINGS">FIG. 8</figref> is a flowchart useful in describing the procedure of power management processing executed in the digital video camera <b>200</b> of the first embodiment. The program for executing the processing described in connection with <figref idref="DRAWINGS">FIG. 8</figref> is stored in the memory <b>81</b> of the system controller <b>8</b> and is executed by the CPU <b>80</b> of system controller <b>8</b>.

0052First, at step S<b>21</b> in <figref idref="DRAWINGS">FIG. 8</figref>, it is determined whether power being supplied from the main power source to the terminal <b>2</b> is sufficient or not in a manner similar to that of step <b>1</b> in <figref idref="DRAWINGS">FIG. 4</figref>. If the power being supplied from the main power source to the terminal <b>2</b> is sufficient, control proceeds to step S<b>22</b>, where the switch <b>7</b> is opened, to step S<b>23</b>, where the switch S<b>6</b> is closed, and then to step S<b>24</b>, where power from the main power source is supplied to all blocks of the digital video camera <b>200</b> so that the digital video camera <b>200</b> can operate without any limitation being imposed upon its functions. Control then proceeds to step S<b>25</b>, where the LED <b>61</b> is extinguished to notify the user of the fact that the digital video camera <b>200</b> is not operating as a bus-powered device.

0053If power being supplied from the main power source to the terminal <b>2</b> is insufficient, the control proceeds to step S<b>26</b>. Here it is determined whether the power being supplied from the USB interface <b>4</b> to the terminal <b>3</b> is sufficient, just as step S<b>5</b> in <figref idref="DRAWINGS">FIG. 4</figref>. If the power being supplied from the USB interface <b>4</b> to the terminal <b>3</b> is sufficient, then control proceeds to step S<b>27</b>, where the switch <b>6</b> is opened to cut off the supply of power to block <b>65</b>, and then to step S<b>7</b>, where the switch <b>7</b> is closed. As a result, the power from bus power is supplied only to the system controller <b>8</b>, control panel <b>9</b>, card controller <b>10</b> and USB controller <b>11</b> (block <b>62</b>) of the digital video camera <b>200</b>, so that the power consumed by the entire digital video camera <b>200</b> is reduced (step S<b>29</b>). At step S<b>29</b>, the digital video camera <b>200</b> starts operating as a bus-powered device. At this time the digital video camera <b>200</b> supplies power only to components necessary for processing (image transfer processing in this case) between itself and the USB host (the personal computer <b>300</b> in this case). Control then proceeds to step S<b>30</b>, where the LED <b>61</b> is lit to notify the user of the fact that the digital video camera <b>200</b> is operating as a bus-powered device.

0054In this state also, just as in the case of normal operation at step S<b>24</b>, the system controller <b>8</b> instructs the card controller <b>10</b> to control the writing and reading of the memory card <b>22</b> upon receiving a command, which is for reading/writing image data from/to the memory card <b>22</b>, from the personal computer <b>300</b> via the USB interface <b>4</b> and USB controller <b>11</b>. The data read from the memory card <b>22</b> by the card controller <b>10</b> is converted to data that can be transmitted to the personal computer <b>300</b>, and the data can be output from the USB interface <b>4</b> via the USB controller <b>11</b>.

0055Further, upon receiving a command from the personal computer <b>300</b> via the USB interface <b>4</b> and the USB controller <b>11</b> to write image data to the memory card <b>22</b>, the system controller <b>8</b> accepts the image data, which is sent from the personal computer <b>300</b>, by the USB controller <b>11</b>, converts this data to data that is writable to the memory card <b>22</b> and can write the data to the memory card <b>22</b> under the control of the card controller <b>10</b>.

0056If the power supplied from the USB interface <b>4</b> to the terminal base station <b>3</b> is insufficient, control proceeds from step S<b>26</b> to step S<b>31</b>, where switch <b>6</b> is opened, and then to step S<b>32</b>, where switch <b>7</b> is opened. As a result, supply of power to the digital video camera <b>200</b> is terminated. Control then proceeds to step S<b>33</b>, at which the LED is extinguished to notify the user of the fact that the digital video camera <b>200</b> is not operating as a bus-powered device.

0057In accordance with the second embodiment, as described above, power is supplied only to limited blocks in a case where power from the main power source is insufficient but power from the USB interface <b>4</b> is sufficient. As a result, even in the absence of a main power source, the personal computer can access image data on the memory card that has been inserted into the digital video camera <b>200</b>.

0058Further, the second embodiment is such that when supply of power is by bus power, operation that is not particularly required, such as the operation of image and display blocks, is limited (that is, the blocks are turned off) between the image sensing apparatus proper and an external device connected to it, thereby making it possible implement operation within the specifications of bus power that the USB is capable of supplying. Even if a main power source or the like is not installed in the image sensing apparatus proper, direct-print and card reader operations can be executed with ease.

0059Further, when the image sensing apparatus per se is operating under bus power, the indicator (LED) with which the device proper is provided can readily make the user aware of a state in which the image sensing function of the device itself and the image display function have been turned off (or limited).

Other Embodiments

0060As described above, the object of the invention is attained also by supplying a storage medium storing the program codes of the software for performing the functions of the foregoing embodiments to a system or an apparatus, reading the program codes with a computer (e.g., a CPU or MPU) of the system or apparatus from the storage medium, and then executing the program codes. In this case, the program codes per se read from the storage medium implement the novel functions of the embodiment and the storage medium storing the program codes constitutes the invention. Examples of storage media that can be used for supplying the program code are a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, non-volatile type memory card or ROM, etc.

0061Further, besides the case where the aforesaid functions according to the embodiments are implemented by executing the program codes read by a computer, the present invention covers a case where an operating system or the like running on the computer performs a part of or the entire process in accordance with the designation of program codes and implements the functions according to the embodiments.

0062Furthermore, the present invention covers a case where, after the program codes read from the storage medium are written in a function expansion board inserted into the computer or in a memory provided in a function expansion unit connected to the computer, a CPU or the like contained in the function expansion board or function expansion unit performs a part of or the entire process in accordance with the designation of program codes and implements the functions of the above embodiments.

0063In the illustrated embodiments, a case where the image sensing apparatus is the digital video camera <b>200</b> is described. However, the present invention is not limited to this and can also be applied to various mobile devices such as a digital camera, a cellular telephone or a PDA.

0064As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.

CLAIM OF PRIORITY

0065This application claims priority from Japanese Patent Application No. 2003-303544, filed on Aug. 27, 2003, which is hereby incorporated by reference herein.